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排序方式: 共有894条查询结果,搜索用时 15 毫秒
41.
42.
W P Barclay J J Foerner T N Phillips 《Journal of the American Veterinary Medical Association》1985,186(3):278-279
Axial sesamoid injuries were found in 4 of 18 horses with lateral condylar fractures of the metacarpus or metatarsus. The injuries appeared as axial sesamoid fractures or progressive demineralization of the axial border of one of the sesamoids. None of the horses with axial sesamoid injuries returned to performance soundness. Axial sesamoid injury appeared to be an indication of severe fetlock trauma due to condylar fracture. Such injuries appeared to indicate a poor prognosis for return to performance soundness. 相似文献
43.
R. W. Mullen S. B. Phillips W. R. Raun G. V. Johnson W.E. Thomason 《Journal of plant nutrition》2013,36(5):673-681
Bermudagrass (Cynodon dactylon L.) is a warm season perennial that is well adapted in the southern Great Plains. It is one of the region's most important forage crops used for livestock production, and is commonly grown without legume interseeding. Recent research has investigated ways of improving the quality and quantity of this forage. The objectives of this study were to determine the effect of interseeded legumes and phosphorus (P) fertilizer on bermudagrass pasture forage yield and crude protein content. One experiment was initiated in 1993 in eastern Oklahoma in an established bermudagrass pasture. Red clover (Trifolium pratense L.), ladino clover (Trifolium repens L.), and two varieties of alfalfa (Medicago sativah), ’alfagraze’ and'common’, were interseeded by hand into an established stand of bermudagrass. The effect of P on forage yield and crude protein was evaluated using a 30‐kg P ha‐1 rate applied at establishment versus no applied P. Forage yield was collected three times throughout the growing season each year from 1994 through 1997. When both alfalfa varieties were interseeded into a bermudagrass pasture without applying additional P fertilizer, forage yields for the legume‐grass mixtures decreased below those obtained from the monoculture bermudagrass in the first year of the stand. The alfalfa variety ‘alfagraze’ interseeded into established bermudagrass decreased total forage yield over the entire 4‐yr study. Interseeded red clover and ladino clover increased crude protein of the forage compared with monoculture bermudagrass the first two years of the study, with red clover continuing to increase crude protein in the fourth year. However, when 30 kg P ha‐1 was applied to the bermudagrass prior to establishment of the legumes, no change in yield or protein was observed for both alfalfa varieties’ interseeding treatments versus the unfertilized mixtures. Although forage yield may not be increased, interseeding legumes into established bermudagrass could provide an efficient way to improve pasture crude protein without the use of inorganic fertilizers. However, if alfalfa ('common’ or ‘alfagraze') is interseeded, additional P may need to be applied at legume establishment to prevent possible yield decreases. 相似文献
44.
Zuber MT Smith DE Phillips RJ Solomon SC Neumann GA Hauck SA Peale SJ Barnouin OS Head JW Johnson CL Lemoine FG Mazarico E Sun X Torrence MH Freed AM Klimczak C Margot JL Oberst J Perry ME McNutt RL Balcerski JA Michel N Talpe MJ Yang D 《Science (New York, N.Y.)》2012,336(6078):217-220
Laser altimetry by the MESSENGER spacecraft has yielded a topographic model of the northern hemisphere of Mercury. The dynamic range of elevations is considerably smaller than those of Mars or the Moon. The most prominent feature is an extensive lowland at high northern latitudes that hosts the volcanic northern plains. Within this lowland is a broad topographic rise that experienced uplift after plains emplacement. The interior of the 1500-km-diameter Caloris impact basin has been modified so that part of the basin floor now stands higher than the rim. The elevated portion of the floor of Caloris appears to be part of a quasi-linear rise that extends for approximately half the planetary circumference at mid-latitudes. Collectively, these features imply that long-wavelength changes to Mercury's topography occurred after the earliest phases of the planet's geological history. 相似文献
45.
Steroid profiles of cultured and captive red drum (Sciaenops ocellatus L.) were investigated to evaluate the potential use of circulating sex steroid levels as a tool for gender identification in this species. Cultured 18‐month‐old fish were maintained on a 120‐day shortened photothermal cycle to induce precocious maturation. Additionally, wild‐caught fish were maintained in captivity under simulated natural photothermal conditions from late spring to early fall. Circulating 11‐ketotestosterone (11‐KT) levels were significantly higher in males compared with females during the early stages of gonadal growth in both cultured and captive fish. Plasma testosterone (T) levels showed a similar trend; however, the differences were significant only when males were already producing sperm. 17β‐estradiol (E2) concentrations were low in males and females before gonadal recrudescence but increased significantly with the progression of vitellogenesis in females. These results show that a test using a minimum concentration of circulating 11‐KT could be developed to differentiate between sexes in the early stages of gonadal maturation in red drum. Moreover, plasma E2 concentrations could be used to identify vitellogenic females. The two steroids considered together could help avoid possible error in gender identification due to unusually high levels of certain steroids encountered in some individuals. 相似文献
46.
Several high-intensity synchrotron x-ray sources have been constructed over the past few years in the United States, West Germany, Great Britain, Japan, France, Italy, and the Soviet Union. Crystallographers have begun to use these facilities for experiments that take advantage of the characteristics of synchrotron radiation, namely, a broad distribution of wavelengths, high intensity, low divergence, strong polarization, and a pulsed time structure. In addition to more familiar diffraction experiments on single crystals and powdered samples, new types of crystallographic studies, for example, energy-dispersive and surface diffraction studies, have progressed rapidly with more general accessibility of synchrotron sources. These high-intensity sources allow diffraction experiments to be performed on very small crystals or on large biological molecules, and permit weak magnetic scattering to be detected Anomalous dispersion experiments can exploit he ability to vary the wavelength of the radiation, and the pulsed time structure of the beam makes possible fast time-resolved experiments. Because of the availability of synchrotron x-radiation, these and other kinds of experiments will be in the forefront of crystallographic research for the next several years. 相似文献
47.
M S Hand E Hunt R W Phillips 《Veterinary Clinics of North America: Food Animal Practice》1985,1(3):589-608
A rather long list of broad generalizations exist regarding milk replacers for calves. At least two more general statements should be added to that list. Most broad generalizations regarding milk replacers should be applied cautiously; and if young calves (less than 2 to 3 weeks) are to be fed milk substitutes, the products should be of high quality. Our primary goal in feeding baby calves should be health oriented--that is, not to pre-dispose to or cause diarrhea through diet. This means using milk-source ingredients in milk substitutes targeted for young calves. The preponderance of data presented in this article underscores that statement. Milk replacers containing nonmilk sources of major nutrients are better fed to older calves. 相似文献
48.
49.
Dr. R. Plarre Maja Pöschko Sabine Prozell Andrea Frank R. Wohlgemuth J. K. Phillips 《Journal of pest science》1997,70(3):45-50
Tineola bisselliella is a common pest on natural fabrics of economic importance. Two commercially available repellents for use against adult webbing clothes moths were tested for their efficacy in dual- and no-choice bioassays. Oil of cloves and citral in combination, as well as citronellol scented with oil of lavender showed promising repellent effects for 4 weeks when applied in small compartments of a wardrobe. Although the repellent efficacy was not 100% under the conditions tested, the usage of essential oils in combination with other infestation prevention techniques is discussed.
This article reports the results of research only. Mention of a proprietary product or pesticide does not constitute an endorsement or a recommendation for its use by the Federal Biological Research Centre for Agriculture and Forestry or by the USDA-ARS. 相似文献
Zusammenfassung Die KleidermotteTineola bisselliella Hum. ist einer der wirtschaftlich bedeutenden tierischen Wollzerstörer. Auch Pelze, Felle, Polsterhaare und Federn werden von dem weit verbreiteten Kleinschmetterling aus der Familie der Tineidae befallen. In der Praxis gilt es vor allem Kleidungsstücke, die z. B. saisonbedingt für längere Zeit ungenutzt in einem Kleiderschrank aufbewahrt werden, vor dem Befall durch die Kleidermotte zu schützen. Hierfür stehen dem Verbraucher neben den konventionellen Bekämpfungsmitteln mit den Wirkstoffen Kampfer, Naphthalin und Paradichlorbenzol sowie pyrethrum- und pyrethroidhaltige Mittel auch Präparate zur Verfügung, die auf die repellierende Wirkung von ätherischen Ölen zurückgreifen. Die abstoßende Wirkung von Nelkenöl in Kombination mit Citral und von Citronellol parfümiert mit Lavendelöl auf die Falter der Kleidermotte wurde auf vergleichbare Eigenschaften untersucht. In Wahlversuchen wurden deutliche Repellent-Wirkungen der Mottenschutz-Präparate sichtbar. Die Präparate zeigten gute Wirkungen, wenn sie zum Schutz gegen den Zuflug von Kleidermotten an wollhaltigen Stoffen in kleinen Kompartimenten eines Kleiderschrankes ausgelegt waren. Auch in Zwangsversuchen hatte dieser Befund zum Teil Bestand. Bei längeren Versuchszeiten wurden allerdings verstärkt Fraßschäden durch Larven an den Wollstoffen festgestellt. Dies ist darauf zurückzuführen, daß Mottenweibchen nicht mehr in dem Maße repelliert wurden und ihre Eier an den Stoffen ablegten.
This article reports the results of research only. Mention of a proprietary product or pesticide does not constitute an endorsement or a recommendation for its use by the Federal Biological Research Centre for Agriculture and Forestry or by the USDA-ARS. 相似文献
50.
An experiment was conducted in southern Chile to study the effect of tree cover (0 or 200 stems of 13-year-old Pinus radiate/ha), grazing severity (8 or 12 cm height at commencement of grazing by sheep) and fertilizer application rate (low or high)
on the establishment and growth of Lotus uliginosus and Trifolium subterraneum, when sown in conjunction with Festuca arundinacea. The establishment of both legumes was greater in the agroforestry than the open field, and the percentage of viable seeds
that were established was greater for Trifolium than Lotus. Festuca established better when sown in conjunction with Lotus in the open field. During the two years after stand establishment there was a greater reduction in the ground cover and dry
matter (DM) yield of both legumes, but in particular Trifolium, in the agroforestry than in the open field. In the second year of grazing Trifolium contributed less than 9% of total DM yield in the agroforestry, compared with 22% for Lotus. The ground cover of Lotus was increased by a tall grazing height in the agroforestry, whereas Trifolium increased its cover when the grazing height was short. Additional fertilizer at establishment had a greater effect in increasing
herbage yield in the open field than in agroforestry. It is concluded that both Lotus and Trifolium establishments are greater in agroforestry than in an open field, but that in agroforestry there is a reduction in legume
yield over time, particularly of Trifolium.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献